The axon is a specialized appendage of the nerve cell that lacks visable ribosomes; yet, it is capable of extramitochondrial protein synthesis. The purpose of the proposed investigation is to study the macromolecular machinery concerned with renewal and growth of the axon and to ascertain the roles of the cell body, Schwann cell and peripheral field of innervation in controlling and regulating this machinery. The specific aims are: (1) to fractionate and to characterize the protein synthesizing machinery of the axon; (2) to microfractionate axonal proteins synthesized locally and compare them with those synthesized in cell bodies or Schwann cells and transported to the axon; (3) to microfractionate and compare proteins synthesized in the normal axon with those synthesized in regenerating axon terminals; (4) to microfractionate and compare proteins transported to the axon from normal and chromatolysed nerve cell bodies; (5) to microfractionate and compare RNA classes synthesized in normal nerve cells with those synthesized in chromatolysed nerve cells; (6) to ascertain the origin of axonal RNA; (7) to characterize and compare RNA classes synthesized in Schwann cells from regions of normal nerve, injured nerve, and decentralized portion of nerve after Wallerian degeneration; and (8) to ascertain the roles of the cell bodies and local Schwann cells in causing the circumscribed stimulation of protein synthesis of regenerating axon terminals.